This invention relates to an electronic connector and in particular to means for retaining or securing an electronic connector to a substrate such as a printed circuit board.
Electronic connectors are generally provided with projections such as lips or lobes on the end faces of the insulating housing. The connector can then be secured to a circuit board substrate by means of, for example, a screwed or riveted joint in an aperture formed in these projections and in the substrate. Examples of prior art securing means are disclosed in U.S. Pat. Nos. 4,628,410, 4,691,971 and 4,695,106.
Electronic circuits are currently accommodated as far as possible in a modular manner on printed circuit boards of standard dimensions. Electrical connections between the individual modules and/or other electronic equipment are preferably achieved by means of connectors. Due to the need for miniaturization, and due to the relatively greater density of the integrated circuits today, a large number of electronic modules can be disposed on a printed circuit board. As a result, each such module can carry out a large number of functions. This means, however, that the number of electrical connections to other modules also increases.
In the effort to achieve the highest possible contact element density, i.e. the greatest possible number of contact elements per volume unit, the above-mentioned projections for securing the connector on a substrate constitute a limiting factor. The space taken up on a substrate by these projections cannot be used for fitting circuit elements or contact elements. These projections also make it impractical to fit several connectors of standard dimensions on a substrate end-to-end with their end boundary walls adjacent to each without losing one or more positions otherwise available for contact elements for the purpose of forming a connector of desired dimensions. In trade literature, this is also known as end-to-end stacking.
A more recent prior art connector described in U.S. Pat. No. 4,826,422 granted May 2, 1989 employs a solder clip with a projection or solder tail projecting from the bottom of the connector housing. The solder tail is inserted into a hole on a printed circuit board where it is soldered to secure the connector. The metal clip has a wide, flat base which must be inserted in a recessed channel in the bottom wall of the connector housing. There must, however, be sufficient space in the bottom wall to receive the flat plate of the solder clip.